I am getting new warning on my old OSX app. I am using OSX 10.10 and I am not quite sure where the problem is. Can someone help?
The actual warning is Property type 'id is incompatible with type id inherited from NSTextField
#import <Cocoa/Cocoa.h>
#import "HyperlinkTextFieldDelegate.h"
#interface HyperlinkTextField : NSTextField <NSTextFieldDelegate>
#property (assign) id <HyperlinkTextFieldDelegate> delegate; <--- warning showing up here
#end
The main implementation is
#interface HyperlinkTextField ()
#property (nonatomic, readonly) NSArray *hyperlinkInfos;
#property (nonatomic, readonly) NSTextView *textView;
- (void)_resetHyperlinkCursorRects;
#end
#define kHyperlinkInfoCharacterRangeKey #"range"
#define kHyperlinkInfoURLKey #"url"
#define kHyperlinkInfoRectKey #"rect"
#implementation HyperlinkTextField
#synthesize delegate;
And the delegate file is
#import <Foundation/Foundation.h>
#protocol HyperlinkTextFieldDelegate <NSObject>
- (void) barLinkClicked: (id) sender;
#end
NSTextField already has a delegate property, and it is typed as id<NSTextFieldDelegate>. Thus, your HyperinkTextField, which is a subclass of NSTextField, inherits this property, just as the error message clearly tells you. You cannot override this inherited property and type it as id<HyperlinkTextFieldDelegate> where that is a different type.
Related
So I'm trying to access the property isPortClosed(BOOL) in SerialPortController and its giving me an error, I'm kinda new to objective-c. I feel like this should work as I've got a reference to the class with *port. Here is a link to the project.
Error messages: ~/GroundStation/GroundStation/ViewController.m:16:22: Property 'isPortClosed' not found on object of type 'SerialPortController *'
#import <Cocoa/Cocoa.h>
#import "SceneView.h"
#import "SerialPortController.h"
#interface ViewController : NSViewController
#property (strong) IBOutlet SerialPortController *port;
#property (weak) IBOutlet SceneView *accelSceneView;
#end
#import "ViewController.h"
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
while(!self.port.isPortClosed) {
}
}
- (void)setRepresentedObject:(id)representedObject {
[super setRepresentedObject:representedObject];
// Update the view, if already loaded.
}
#end
SerialPortController.h class
#import <Foundation/Foundation.h>
#import <ORSSerial/ORSSerial.h>
#interface SerialPortController : NSObject <ORSSerialPortDelegate>
#property (nonatomic, strong) ORSSerialPort *serial;
#property (nonatomic, strong) ORSSerialPortManager *serialPortManager;
#property (nonatomic) NSInteger xAngle;
#property (nonatomic) NSInteger yAngle;
#property (nonatomic) NSInteger zAngle;
#property (nonatomic) NSString *stringBuffer;
#property (nonatomic) BOOL isPortClosed;
#end
From the downloaded project I see that you have two SerialPortController class definitions (one at the root directory, and one in /GroundStation/), and the latter doesn't have any public properties. You should have only one SerialPortController class definition linked in your project (the one with the public properties).
I am stuck with this problem. I have the following .h file:
#import <UIKit/UIKit.h>
#protocol MapSettingsViewDelegate
- (void)settingsDidUpdate:(BOOL)scheme;
#end
#interface MapSettingsViewController : UIViewController
#property (nonatomic, assign) id <MapSettingsViewDelegate> delegate;
#property (nonatomic, strong) IBOutlet UINavigationBar *navBar;
#property (nonatomic, strong) IBOutlet UINavigationItem *titleItem;
#property (nonatomic, strong) IBOutlet UITableView *TableView;
- (id)init;
- (IBAction)saveAction:(id)sender;
#end
When I declare the following:
#interface MapViewController : UIViewController <MapSettingsViewDelegate>
The compiler complains with the following message:
Cannot find protocol declaration for 'MapSettingsViewDelegate'
I have the same kind of delegate declaration in other files in the same project that are compiled without a glitch. I spent the last four hours trying to figuring out what I am doing wrong. Cleaning the project does not nothing.
Problem solved. As suggested in this answer, I created a new class with a different name and copied all coded from the previous class. Worked flawlessly. It seems XCode lost track of something.
You are running into preprocessor problems. Both of your classes import each other. I think you can solve this by adding #class below your protocol declaration as shown below; and moving your #import "mapViewController.h" line into MapSettingsViewController.m file. The #class tells the compiler that you will include the class content somewhere else (in the .m file).
Note that, on the top of your MapViewController.h class file you can include #import "MapSettingsViewController.h" just like normal. Hope this help. I ran into the same problem myself earlier.
#import <UIKit/UIKit.h>
#protocol MapSettingsViewDelegate
- (void)settingsDidUpdate:(BOOL)scheme;
#end
#class MapViewController
#interface MapSettingsViewController : UIViewController
#property (nonatomic, assign) id <MapSettingsViewDelegate> delegate;
...
...
Import the MapSettingsViewController.h file
I have custom UIView class GestureView. I have a forward declaration for this class and it's delegate below. I have imported GestureView.h in .m file. This works fine but iOS gives warning message saying "Cannot find protocol definition for GestureViewDelegate". If I remove forward declaration it gives same warning message as error. I don't want to import GestureView.h from ContainerViewController.h as I usually imports stuffs in .m file. Could someone please explain what's wrong in following class structure?
ContainerViewController.h
#import <UIKit/UIKit.h>
#class DividerView;
#class GestureView;
#protocol GestureViewDelegate;
#interface ContainerViewController : UIViewController<GestureViewDelegate>
#property (strong, nonatomic) IBOutlet GestureView *topContentView;
#end
GestureView.h
#import <UIKit/UIKit.h>
#protocol GestureViewDelegate;
#interface GestureView : UIView
- (void)initialiseGestures:(id)delegate;
#end
#protocol GestureViewDelegate <NSObject>
#required
- (void)GestureView:(GestureView*)view handleSignleTap:(UITapGestureRecognizer*)recognizer;
#end
I like that you're trying to avoid imports in header files: very good practice. However, to fix your bug you can just make your code even better! In my opinion it's not really necessary that your ContainerViewController class outwardly declares that it supports GestureViewDelegate protocol, so you should move this into your implementation file. Like so:
GestureView.h
#import <UIKit/UIKit.h>
#protocol GestureViewDelegate;
#interface GestureView : UIView
- (void)initialiseGestures:(id <GestureViewDelegate>)delegate;
#end
#protocol GestureViewDelegate <NSObject>
#required
- (void)gestureView:(GestureView *)view handleSingleTap:(UITapGestureRecognizer *)recognizer;
#end
ContainerViewController.h
#import <UIKit/UIKit.h>
#class GestureView;
#interface CollectionViewController : UIViewController
// this property is declared as readonly because external classes don't need to modify the value (I guessed seen as it was an IBOutlet)
#property (strong, nonatomic, readonly) GestureView *topContentView;
#end
ContainerViewController.m
#import "ContainerViewController.h"
#import "GestureView.h"
// this private interface declares that GestureViewDelegate is supported
#interface CollectionViewController () <GestureViewDelegate>
// the view is redeclared in the implementation file as readwrite and IBOutlet
#property (strong, nonatomic) IBOutlet GestureView *topContentView;
#end
#implementation ContainerViewController
// your implementation code goes here
#end
Try this way, and please reply if it works or not.
GestureView.h
#import <UIKit/UIKit.h>
#protocol GestureViewDelegate <NSObject>
#required
- (void)GestureView:(GestureView*)view handleSignleTap:(UITapGestureRecognizer*)recognizer;
#end
#interface GestureView : UIView
- (void)initialiseGestures:(id)delegate;
#end
ContainerView.h
#import <UIKit/UIKit.h>
#class DividerView;
#class GestureView;
/*#protocol GestureViewDelegate;*/ //NO NEED TO WRITE THIS
#interface ContainerViewController : UIViewController<GestureViewDelegate>
#property (strong, nonatomic) IBOutlet GestureView *topContentView;
#end
In the following example, is the line NSObject *_propertyName; required?
.h
#interface ClassName
{
NSObject *_propertyName;
}
#property (nonatomic, retain) NSObject *propertyName;
#end
.m
#implementation ClassName
#synthesize propertyName = _propertyName;
#end
I find that if I exclude NSObject *_propertyName; but keep #synthesize propertyName = _propertyName; everything works. Here's an example of what I'm talking about:
.h
#interface ClassName
#property (nonatomic, retain) NSObject *propertyName;
#end
.m
#implementation ClassName
#synthesize propertyName = _propertyName;
#end
I've tested and seen that the property still works. I nearly always see code that includes the line NSObject *_propertyName;. Is there something I'm missing here?
You're not missing anything. Starting with the newer runtimes (newer iOS Simulator, x86_64 and ARM) you no longer need to manually declare an ivar. Prior to that on i386 and PPC you had to manually declare your ivars.
I seem to be getting a new error when using LLVM Compiler 2.0, which I haven't had before.
I have a protocol called DTGridViewDelegate defined as:
#protocol DTGridViewDelegate <UIScrollViewDelegate>
I have a property called delegate on DTGridView (a subclass of UIScrollView, which itself has a delegate property). This is defined as:
#property (nonatomic, assign) IBOutlet id<DTGridViewDelegate> delegate;
Now the message I get is:
DTGridView.h:116:63: error: property type 'id<DTGridViewDelegate>' is incompatible with type 'id<UIScrollViewDelegate>' inherited from 'UIScrollView'
Because I had said that the DTGridViewDelegate conforms to UIScrollViewDelegate, I thought that this would be ok to override this property in this way, and indeed this is the first compiler to suggest there is a problem.
I have fixed the error by declaring the property as such:
#property (nonatomic, assign) IBOutlet id<DTGridViewDelegate, UIScrollViewDelegate> delegate;
I am wondering whether this is a compiler issue?
Your setup looks like the same one used in the case of UITableView inheriting from UIScrollView. The UITableViewDelegate protocol inherits from UIScrollViewDelegate protocol.
I set up the following which compiles fine:
// .h
#protocol ParentClassDelegate
-(NSString *) aDelegateMethod;
#end
#interface ParentClass : NSObject {
id delegate;
}
#property(nonatomic, assign) IBOutlet id <ParentClassDelegate> delegate;
#end
//.m
#implementation ParentClass
#synthesize delegate;
-(id) delegate{
return #"Parent delegate";
}//-------------------------------------(id) delegate------------------------------------
-(void) setDelegate:(id)someObj{
delegate=someObj;
}//-------------------------------------(id) setDelegate------------------------------------
#end
//.h
#protocol ChildClassDelegate <ParentClassDelegate>
-(NSArray *) anotherDelegateMethod;
#end
#interface ChildClass : ParentClass{
}
#property(nonatomic, retain) IBOutlet id <ChildClassDelegate> delegate;
#end
//.m
#implementation ChildClass
//#synthesize delegate;
-(id) delegate{
return #"childDelegate";
}//-------------------------------------(id) delegate------------------------------------
-(void) setDelegate:(id)someObj{
delegate=someObj;
}//-------------------------------------(id) setDelegate------------------------------------
#end
Not sure what is causing your problem. I would note that in the header the UITableViewDelegate protocol looks like:
#protocol UITableViewDelegate<NSObject, UIScrollViewDelegate>
... so maybe the compiler likes things more explicit sometimes.
I would suggest a clean and build. That solves a lot of problems.
Since there isn't a formal Objective-C language specification, it's impossible to say whether the compiler is behaving properly. All we can say is that Apple's gcc doesn't seem to have a problem with the above scenario, though it's conceptually unsound as it can break Liskov substitution, since delegate is covariant from UIScrollView to DTGridView (though covariance is just as much a problem). What would happen if you passed a DTGridView to code expecting a UIScrollView, which then proceeded to set delegate to an object that conformed to UIScrollViewDelegate but not DTGridViewDelegate?